The high-velocity clouds and the Magellanic Clouds

The high-velocity clouds and the Magellanic Clouds

From an analysis of the sky and velocity distributions of the high-velocity clouds (HVCs) we show that the majority of the HVCs has a common origin. We conclude that the HVCs surround the Galaxy, forming a metacloud of ∼ 300 kpc in size and with a mass of ∼ 3×109 M⊙, and that they are the product of a powerful “superwind” (about 10 58 ergs), which occurred in the Magellanic Clouds about 570 Myr...

The Magellanic Clouds Newsletter

Compact High Velocity Clouds

We summarize the observed properties of the CHVC population, which provide strong evidence for source distances in the range 200– 1000 kpc. At these distances, the population corresponds to strongly dark-matter dominated sub-dwarf galaxies still accreting onto the more massive Local Group systems. Recent searches for faint associated stellar populations have revealed red-giant candidates for wh...

High-velocity Clouds and the Local Group

I examine some of the evidence relevant to the idea that high-velocity clouds (HVCs) are gas clouds distributed throughout the Local Group, as proposed by Blitz et al. (1999) and Braun & Burton (1999). This model makes several predictions: a) the clouds have low metallicities; b) there should be no detectable Hα emission; c) analogues near other galaxies should exist; and d) many faint HVCs in ...

Superbubbles in the Magellanic Clouds

Superbubbles that result from the stellar winds and supernovae of OB associations probably play a fundamental role in the structure and energetics of the ISM in star-forming galaxies. Their influence may also dominate the relationship between the different interstellar gas phases. How do superbubbles form and evolve? How do they affect the local and global ISM? The Magellanic Clouds provide a s...